1. Field of the Invention
The present invention is generally related to utility support structures, and more particular to ambulatory apparatus adapted to support medical supplies or equipment.
2. Prior Art
The purpose of the present invention is to provide an improved apparatus which can support pumps, tubes, hoses, containers of fluid or other accessories specifically for use in medical applications. To be used for the defined applications, the equipment must be ambulatory and thereby be easily moved from location to location. Because of the environment in which the present invention is intended to be used, it must exhibit a high degree of stability. Loads which must be supported by the apparatus can be heavy and therefore difficult to handle. In addition, where the load comprises a fluid which is being dispensed to a patient, pressure requirements dictate the load be vertically moveable to the selected height.
The classical device taught by the prior art is typically defined by a vertical pole supported by three or four equally spaced legs coupled at the lower terminus of the pole. Even if the supporting legs are provided with ambulatory casters, the device is susceptible of overturning since support is provided only at minimum intervals of 90.degree. of arc. To support a load, a vertical standard is provided with fixed vertical couplings from which medical equipment or fluids are suspended. The problems inherent in this type of device are evident. Under the conditions which typically exist in operating theaters or otherwise, the availability of large volumes of fluid are often required. The devices taught by the prior art require medical personnel to manually lift or otherwise change the position of the fluid reservoirs, a task which can be difficult and often dangerous under the conditions of use.
Another device taught by the prior art provides for the mechanical adjustment of a plurality of hanger supports, each of which is adapted to position a container of fluid. Each hanger support is directly coupled to a locking assembly or positioner, the movement of which is directly reflected in the repositioning of the hanger support. Although this device provides for the mechanical repositioning of a supported load, it provides no mechanical advantage to the user thereby making it extremely burdensome for use in applications requiring the support of heavy loads.
The present invention substantially resolves those problems exhibited by the devices disclosed in the prior art. A stable, ambulatory vertical standard comprises a plurality of adjacent tracks, each track being adapted to support an independent fluid hanger. Each fluid hanger is coupled to a pulley assembly disposed within a positioning track. The pulley assembly provides a mechanical advantage of at least 2:1 while simultaneously reversing the direction of force which must be used to move the fluid hanger upwardly or downwardly. Upward or downward movement of each fluid hanger is determined by the selected arrangement of a positioning arm. The positioning arm is coupled to the pulley assembly, the direction of movement of the respective fluid hanger being inversely related to the direction of the movement of the positioning arm. This allows the user to effectively employ his or her weight to impose upward movement to a fluid container which is suspended from a fluid hanger.
To enhance the stability of the present invention, the vertical standard is coupled to an inverted base. The base comprises a hub and a complement of at least five uniformly spaced supporting legs radiating outwardly from the hub and lower terminus of the vertical standard. The end of each leg opposite the hub is coupled to a conventional caster. Stability is provided by vertically disposing the interface between the standard and the hub at a level which is lower than the interface between the supporting legs and the casters. The inverted interface at the hub lowers the center of gravity of the assembled apparatus.